Increasing the efficiency of water-recirculation systems operation

Conclusions To raise the operational efficiency of water recirculation systems, it is necessary to develop a closed water supply system and to carry out treatment with reagents.Of all the investigated inhibitors for recirculation water in the manufacture of man-made fibre, the zinc-bichromate-phosphate inhibitor is the most effective.Use of the zinc-bichromate-phosphate inhibitor reduces the corrosion rate five- to seven-fold depending in the physicochemical composition of the recirculation water, and reduces the corrosion resistance figure by two units.The inhibitor is effective over a wide range of concentrations of dissolved mineral salts (2000–10,000 mg/liter).Translated from Khimicheskie Volokna, No. 3, pp. 55–57, May–June, 1985.     

Increasing the efficiency of the extrusion process

The article presents constructional methods of increasing the efficiency of the polymer extrusion process. Increasing the efficiency of the polymer extrusion process consists in the increase of the flow rate of the processed polymer and the energy efficiency of polymer processing extruders and the decrease of the specific energy consumption and the pulsation of the flow rate and polymer pressure, as well as quality improvement of the received extrudate as a result of better homogenization of mechanical and thermal properties and polymer structure. Therefore, the improvement of the constructional solution of the screw and barrel of the extruder plasticating system was discussed. The improvement of the construction of the screw lies in using the active and passive grooved barrel section. Original constructional solutions of the active grooved section with both longitudinal and helical grooves were shown. The devices increasing the efficiency of the extrusion were also shown, which included a screen changer, a melt pump, and a static mixer. Appropriate conclusions were drawn. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers     

Increasing nutrient use efficiency in rice with changing needs

The use of N fertilizer in Asia has increased from 24 to 39% of the world's total consumption between 1973 and 1987/88. Approximately 60% of the N fertilizer consumed in Asia is used on rice (Oryza sativa L.). However, the N applied to rice, primarily as urea, is not effectively utilized by the crop. Ammonia volatilization is recognized as a major mechanism of N loss, causing ineffective N utilization. Basal incorporation of urea without standing water; deep placement of urea; and modification of urea with algicides, urea inhibitors or coatings are strategies to reduce ammonia loss. Loss of N by nitrification-denitrification may be a serious problem particularly when soil is dried between rice crops, then flooded for the subsequent rice crop. The use of organic N sources, such as green manure and organic manures, as partial substitutes of inorganic N fertilizer is receiving renewed research interest.The use of P fertilizers for rice is most necessary on Oxisols and Ultisols with high P-fixing capacity. Phosphate rock and partially acidulated phosphate rock are alternatives to soluble P sources used on these soils. Response to K is normally highest on light-textured soils. The limited available information suggests that in lowland rice-upland crop rotations, K fertilizers should be applied to the non-rice crop. Zinc deficiency can be overcome through (a) use of varieties more tolerant to zinc deficiency, (b) application of zinc sulfate, and (c) dipping seedling roots in a zinc oxide suspension.Increasing use of S-free fertilizers, intensive cropping, and use of high yielding rice varieties have led to S deficiency in many rice growing countries. Sulfur deficiency can be corrected by applying S-containing materials even with elemental S. Residual effects have also been reported even at a low rate of 20 kg S/ha. Thus, S does not need to be applied every season.To address the unresolved integrated nutrient management issues, both strategic and applied research are required on interacting soil-plant-water-nutrient-climate processes. Long-term sustainability is one of the parameters that must be considered in evaluating the desirability of alternative rice technologies.Paper presented at the Fertilizer Asia Conference and Exhibition, 15–18 October 1989, Manila.     

Economic reform and production efficiency

Glass and Ceramics -